Without seeing the rest of your code I can't be sure the root of the problem, but it could be the form is not wrapped inside the form function. If the above doesn't seem to work for you, perhaps pastie your Widget Class?

I should perhaps add that my widget class has a variable w_arg, an array of defaults! E.g.

Thanks for your input Stephen, it is wrapped correctly inside the form function, I also have a bunch of other plain text box options which are working flawlessly, I also have defaults defined in a very similar way to you. The problem appears to be specifically related to drop down options and check boxes!
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DannyJan 23 '12 at 12:58